Initial stab at adding support for SaxonEE
B-47227 Test Repose Translation of XML with embedded JSON

Add the xsl-engine attribute to translation.cfg.xml to enable SaxonEE which allows XSL 3.0
and the ability to parse embedded JSON.

Added JMeter tests to demonstrate that JSON is parsed in the request & response & XML
is modified accordingly.
B-47227 - Test Repose Translation of XML with embedded JSON

A bug in SaxonEE 9.4 causes a license to be required for IdentityTransformer, even when it is not required.
This is fixed in 9.5, until then we use the XalanC Transformer in place of SaxonHE for Identity transforms.
This same procedure is used in api-checker to get around this issue.
When adding SaxonEE 9.5, need to update all sections tagged with TODO_SAXON_WORKAROUND
Merge pull request #510 from usnavi/master

B-47227 Test Repose Translation of XML with embedded JSON